Scholars of different academic ages under each research topic used heat maps for their research methods

      We have drawn three bubble heat maps of different research topics and research methods used according to the different age groups in which the scholars are located. Where each bubble color represents the logarithm of the frequency of the research method used by the scholar on a certain topic. The darker the color, the more frequently the method is used in the corresponding topic.

# Research Method Number Method
1 M1 bibliometrics
2 M2 content analysis
3 M3 delphi study
4 M4 ethnography/field study
5 M5 experiment
6 M6 focus groups
7 M7 historical method
8 M8 interview
9 M9 observation
10 M10 questionnaire
11 M11 research diary/journal
12 M12 theoretical approach
13 M13 think aloud protocol
14 M14 transaction log analysis
15 M15 webometrics
16 M16 other methods

# Research Topic Number Topic
1 T0 Scientometrics
2 T1 Information Theory
3 T2 Information Retrieval
4 T3 Text Mining
5 T4 Library Services
6 T5 Digital Information Resources
7 T6 Information Retrieval Models and Evaluation
8 T7 Information Search Behavior
9 T8 Knowledge Management
10 T9 Library Education/Information Literacy
11 T10 International Cooperation
12 T11 Bibliometric Analysis
13 T12 Library Policy/Public Services
14 T13 Health Information Services
15 T14 Academic Productivity
16 T15 Social Media/Emotion Analysis
17 T16 Academic Publishing
18 T17 Information Dissemination
19 T18 User Information Behavior
20 T19 Data Security Management